Noah Webster's New International Dictionary of the English Language

1. (superl.) Not bright or distinct; wanting luminousness or clearness; obscure in luster or sound; dusky; darkish; obscure; indistinct; overcast; tarnished.

2. (superl.) Dull of apprehension; of weak perception; obtuse.

3. (v. t.) To render dim, obscure, or dark; to make less bright or distinct; to take away the luster of; to darken; to dull; to obscure; to eclipse.

4. (v. t.) To deprive of distinct vision; to hinder from seeing clearly, either by dazzling or clouding the eyes; to darken the senses or understanding of.

5. (v. i.) To grow dim.